Fuel cooler, automotive vehicle comprising such a fuel cooler and method for producing such a fuel cooler

ABSTRACT

The present invention relates to a fuel cooler comprising at least one cooling module having a flow channel formed therein, the cooling module comprising at least one joining means for joining with at least one further cooling module.

The present invention relates to a fuel cooler, an automotive vehicle comprising such a fuel cooler, and a method for producing such a fuel cooler.

In diesel engines, diesel fuel returned from the engine into the tank may have temperatures of up to 135° C., whereby especially during long operation periods the temperature of the fuel inside the tank may rise. That is why the diesel fuel returned into the tank is cooled.

A fuel cooler for automotive vehicles with diesel engines is known from DE 197 02 440 A1.

Said fuel cooler is composed of a tube which is bent several times and forms a plurality of parallel-arranged flow channels integrally connected to the U-bent tube sections. This repeatedly bent tube is mounted on a built-on plate which comprises a recess corresponding to the contour of the tube. The tube is fitted into said recess and soldered therewith. In a further fuel cooler suggested in DE 197 02 440 A1, the parallel flow channels are made integral with the built-on plate, the respectively open ends of the flow channels being interconnected by tube bends.

The known fuel cooler is intended for mounting in the area of the longitudinal sills of an automotive vehicle or at another suitable place on the vehicle bottom in such a manner that headwind can flow towards the cooling fins provided on the fuel cooler.

The known fuel cooler has the drawback that it requires a predetermined fixed constructional space and can only be provided in the area of the vehicle bottom due to its geometry. In the area of the vehicle bottom, however, the fuel cooler is exposed to parts possibly thrown up by the wheels.

Furthermore, many manufacturing steps are needed for producing the known fuel cooler, e.g. bending the tube, stamping the built-on plate, and soldering the tube to the plate. Moreover, the known fuel cooler is not very flexible with respect to the design of the cooling capacity and the flow resistance.

It is the object of the present invention to provide a fuel cooler which can be easily adapted to the given constructional space inside the automotive vehicle. Furthermore, an automotive vehicle with such a fuel cooler and a method for producing such a fuel cooler shall be provided.

As for the fuel cooler, the object is achieved according to the invention by the subject matter of claim 1. As for the automotive vehicle and the method, respectively, the object is achieved according to the invention by the subject matters of claims 11, 12.

The invention has the advantage that due to its modular construction the fuel cooler can be flexibly adapted to the constructional space given in the automotive vehicle, so that said space can be used in an optimum manner. Due to the modular construction of the fuel cooler the range of possible constructional designs is enlarged on the whole because the arrangement of the cooling fins, for instance, can be freely configured, so that the construction of the fuel cooler can be adapted to the constructional conditions or special requirements of the customers. Furthermore, the cooling capacity and the flow resistance can be varied easily, for instance by realizing a meandering construction of the fuel cooler with several cooling modules, which may also be arranged in parallel or in series. Moreover, the manufacturing steps which have so far been required, i.e. soldering, stamping or punching, are not needed because the individual cooling modules are produced by extrusion molding or impact extrusion and are combined with one another to form the fuel cooler. In addition, inexpensive semifinished products can be used as cut goods from which the individual cooling modules can be made, resulting in further economic advantages.

Preferably, the cooling module comprises two joining means. It is thereby possible to join any desired number of cooling modules with one another.

The two joining means may have the same shape, so that the cooling module or cooling modules can be produced in a particularly simple manner. It may here be that at least two cooling modules are joined by a joining element which is in engagement with one of the two joining means of the one cooling module and with one of the two joining means of the other cooling module. The use of a joining element for joining the cooling modules makes it possible to improve the mechanical stabilization of the fuel cooler.

Alternatively, the one joining means may be configured in the form of a tongue and the other joining means in the form of a groove. Said configuration of the cooling module(s) permits a direct joining of the cooling modules with one another, the tongue of the one cooling module engaging into the groove of the other cooling module. Said embodiment of the invention is inexpensive because comparatively few components are needed for producing the fuel cooler.

The cooling module(s) may be made tubular, so that continuous semifinished products can be used for producing the individual cooling modules, particularly by extrusion molding or impact extrusion.

In a further advantageous embodiment of the invention, a plurality of cooling modules are each connected at the end side by a connecting piece having a flow channel formed therein, the connecting piece comprising at least a number of connecting sections corresponding to the number of the cooling modules. Thanks to the use of such connecting pieces any desired number of cooling modules can be combined with one another in a flexible manner.

The cooling module(s) may comprise cooling fins for improving the cooling capacity.

The invention will now be explained with further details and with reference to the attached schematic drawings, of which:

FIG. 1 is a perspective view of a cooling module for a fuel cooler according to an embodiment of the invention;

FIG. 2 shows an enlarged section of the joining means of the cooling module according to FIG. 1 with a joining element;

FIG. 3 is a front view of a connecting piece of a fuel cooler;

FIG. 4 is a top view on the connecting piece according to FIG. 3; and

FIG. 5 shows an example of a restricted available constructional space which can be optimally used by the fuel cooler according to the invention.

FIG. 1 shows a cooling module 1 of a fuel cooler as is e.g. used in diesel engines of automotive vehicles. The illustrated cooling module 1 is not limited to cooling diesel fuel, but can in general be used for cooling fuel also in other engines.

The cooling module 1 has formed therein a flow channel 2 through which fuel is transported during operation of the engine, with the fuel discharging heat to the environment through the wall of the cooling module 1. In the embodiment shown in FIG. 1, the cooling module 1 has an elongated shape, the flow channel 2 being made tubular, i.e. provided with a circular cross-section. Other geometries of the flow channel are possible with respect to both cross-section and longitudinal shape.

The individual cooling module 1 shown in FIG. 1 may be combined with further cooling modules of a similar structure to obtain a fuel cooler. It is also possible to use the cooling module shown in FIG. 1 without the cooling module being combined with further cooling modules.

Two joining means 3, 4 are provided on the cooling module 1 for joining with further cooling modules. The joining means 3, 4 are made symmetrical, offset by 180°, at both sides of the cooling module 1. Another arrangement of the two joining means 3, 4, e.g. offset by 90° or by another angle, is also possible and depends on the desired geometrical shape of the fuel cooler or on the predetermined form of the available constructional space. Furthermore, it is possible to provide more than two joining means 3, 4, for instance three or four joining means that are mounted in spaced-apart relationship on the cooling module 1 for joining with further cooling modules. It is thereby possible to build up a package of several cooling modules, the form of said package being variable in almost any desired way. Moreover, cooling modules of different lengths may be combined.

The joining means 3, 4 are arranged in the longitudinal direction of the cooling module 1, particularly in parallel with the longitudinal axis. The tubular configuration of the cooling module 1 and the arrangement of the joining means 3, 4 in the longitudinal direction of the cooling module 1 permit an easy manufacture of the cooling module 1, e.g. by extrusion molding or by impact extrusion. To this end the cooling module 1 consists of metal, preferably of aluminum. Furthermore, alloys which can be subjected to extrusion molding or impact extrusion can be used.

In the embodiment shown in FIG. 1, the joining means 3, 4 are configured as a groove-and-tongue system. The joining means 3 which is configured as a tongue is an extension which is T-shaped in cross section and which is integrally connected to the cooling module 1, particularly to the wall of the flow channel 2. The joining means 4 which is arranged opposite to the joining means 4 formed as a tongue is provided as a groove in the example shown in FIG. 1, the groove being made complementary to the tongue of the joining means 3. The groove of the joining means is here formed by two groove walls 4 a, 4 b extending in the longitudinal direction of the cooling module 1, the two groove walls being formed on the cooling module 1.

The cooling module 1 shown in FIG. 1 is adapted to be directly connected to further cooling modules of the same construction; the joining means 3 which is designed as the tongue is here joined with a joining means 4 of a further cooling module, the joining means 4 being configured as a groove.

Instead of the groove-and-tongue system shown in FIG. 1, the joining means 3 may be of a similar configuration, as shown in FIG. 2. For instance, the two joining means 3 may each be formed as extensions of a T-shaped cross-section on the cooling module 1. A joining element 5 which comprises two grooves 5 a, 5 b made complementary to the T-shaped joining means 3 is provided for joining the cooling module 1 with a further cooling module.

In the mounted state, the T-shaped joining means 3 of the one cooling module 1 engages into the complementary groove 5 a of the joining element 5. At the other side of the joining element 5, the T-shaped joining element of a further cooling module (not shown) engages into the complementary groove 5 b, thereby establishing a connection between two cooling modules.

It is also possible to provide T-shaped extensions on the joining element 5 and joining means in the form of complementary grooves on the cooling modules.

The joining element 5 shown in FIG. 2 has side walls of a concave configuration which are adapted to the profile of the cooling module. The connection between two cooling modules is thereby stabilized mechanically. Moreover, the joining element can be made from a heat-insulating material, so that a heat transfer between adjoining cooling modules is prevented. The joining element 5 can also be produced by extrusion molding or impact extrusion.

The cooling module 1 shown in FIG. 1 comprises a plurality of cooling fins 9. It is also possible to construct the cooling module 1 without cooling fins, i.e. as a smooth tube. The illustrated number of five cooling fins 9 at both sides of the cooling module 1 is by way of example. Any desired number of cooling fins is possible. Moreover, position and length of the cooling fins can be varied. For instance, it is possible to arrange the cooling fins of a cooling module in a direction towards the vehicle and the cooling fins of the next cooling module in a direction towards the road surface. Furthermore, a hedgehog-like arrangement of the cooling fins is possible.

The individual cooling modules 1 of a fuel cooler are connected by a connecting piece 6, which is shown in FIGS. 3, 4, at the end side, i.e. at their open ends, the connecting piece 6 comprising a flow channel 7, so that the individual cooling modules 1 communicate with one another. The connecting piece 6 comprises a number of connecting sections 8 corresponding to the number of the cooling modules to be connected. Two cooling modules 1 may be connected by the connecting piece 6 shown in FIGS. 3, 4. A connecting piece 6 with three connecting sections 8 is outlined in FIGS. 3, 4 by broken lines.

Moreover, the connecting piece 6 comprises two free connecting sections 8 provided for connection to a return line leading from the injection pump of the engine to the tank, so that the fuel cooler can be installed between engine and tank.

The connecting piece 6 may be made from plastics by injection molding or also from metal and may have any desired shape. In the present example, the connecting piece 6 is substantially U-shaped. When two cooling modules 1 of different lengths are connected, the connecting piece 6 is provided with connecting sections having different lengths each dimensioned such that the difference in length between the cooling modules is compensated.

The modular construction of the fuel cooler permits an optimum exploitation of the available constructional space. For instance, when the constructional space shown in FIG. 5 has a longer section A and a shorter section B, the available constructional space can be fully exploited by using corresponding long cooling modules 1 adapted to the long section A and shorter cooling modules 1 adapted to the shorter section B.

Of course, the constructional space can be optimally occupied not only in terms of area, but also in terms of space by adapting the individual cooling modules 1 accordingly.

Moreover, the cooling capacity and the flow resistance can be varied through a corresponding selection of the number of the cooling modules 1 used or the length or the flow cross-section of the individual cooling modules.

The cooling modules 1 are produced by extrusion molding or impact extrusion and consist, for this purpose, of alloys which can be subjected to extrusion molding or impact extrusion. For the manufacture of the fuel cooler several cooling modules of the same construction are combined with one another. However, it is also possible to combine different cooling modules with one another, such cooling modules being adapted, for instance, with respect to the arrangement or configuration of the cooling fins 9, to the respective constructional conditions. 

1. A fuel cooler comprising at least one cooling module having a flow channel formed therein, the cooling module comprising at least one joining means for joining with at least one further cooling module.
 2. The fuel cooler according to claim 1, wherein said cooling module comprises two joining means.
 3. The fuel cooler according to claim 2, wherein the two joining means have the same shape.
 4. The fuel cooler according to claim 3, wherein there are at least two cooling modules joined by a joining element which is in engagement with one of the two joining means of the one cooling module and with one of the two joining means of the other cooling module.
 5. The fuel cooler according to claim 2, wherein the one joining means is configured in the form of a tongue and the other joining means in the form of a groove.
 6. The fuel cooler according to claim 5, wherein there are at least two cooling modules which are directly joined with one another, the tongue of the one cooling module engaging into the groove of the other cooling module.
 7. The fuel cooler according to claim 1, wherein the cooling module(s) is/are at made tubular.
 8. The fuel cooler according to claim 7, wherein a plurality of cooling modules are each connected at the end side by a connecting piece in which a flow channel is formed, the connecting piece including at least a number of connecting sections corresponding to the number of cooling modules.
 9. The fuel cooler according to claim 8, wherein the connecting piece is made of plastics or metal.
 10. The fuel cooler according to claim 1, wherein the cooling module(s) comprise(s) cooling fins.
 11. An automotive vehicle comprising a fuel cooler according to claim
 1. 12. A method for producing a fuel cooler according to claim 1, wherein the cooling module is produced by extrusion molding or impact extrusion. 